Disasters are ranked according to both their potential for damage and the likelihood that they will occur in the next five years. An influenza pandemic, for example, is considered both likely and serious, while wildfires are both less damaging and about a hundred times less likely. Disasters sometimes change rank depending on new information—between 2013 and 2015 “public unrest” became less likely, somehow—but the overall list of disasters is generally the same each time. Tsunamis, probably owing to the UK’s lack of seismic activity, have never made it into the register.